A:Answer It's the synthetic leather that seems like eventually it could be prone to cracking, but they're very comfy after being broken in. Initially they were a little pressing on the top of my head where the rubber stap is that keeps them in place, but now they're perfect (worn about ~50hrs) and they're extremely light, I forget I have them on. Luckily it's a solid piece, there's no clips to fold them anywhere which might be seen as a negative to some but for me that's been the main point of failure in other pairs in the past.
Light plastic, synthetic leather, rubber strap to hold them in place.
